S/PDIF vs. USB interface for DAC

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi All,

I've been reading stereophile's very positive review of Wavelenght audio USB DAC, where Art Dudley claimed that USB interface is superior to S/PDIF (Article) ,so I'd like to ask if its true. I'd like to use USB or S/PDIF receivcer with AD1865 DAC, but I don't know which interface is better for SQ.

Thanks

Regards
Robo
 
DarkOne said:
Hi All,

I've been reading stereophile's very positive review of Wavelenght audio USB DAC, where Art Dudley claimed that USB interface is superior to S/PDIF
-----------------------------------------------------------------------------------
Don't know. What I do know is that there are all sorts of problems with usb drivers and computer stability including tendency to interference.

If you ask the computer guys, they will tell you that usb is perefct. But I have not found the kind of rigorous measurements in computer audio as in hifi. The Rightmark test software they use is to me questionable, having compared the results with my hirez FFT analyser.

Having said this, computer audio via usb or spdif does sound ok and fine to me. But it is difficult to compare this with a high end system.

It's time that Stereophile does a proper comparison.
 
I don't want to compare something with highend dac, I just want to make my own dac, which will be as good as I can make it. Maybe it will be better, maybe worse, time and final result will show. I just wanted to ask if somebody compared these two interfaces. I guess that S/PDIF is much easier to implement, but I want to make maximum for sq.

Here's part of that article, which made me think about interfaces:
According to Rankin, the S/PDIF environment is more prone to unwanted variations in the frequency of the incoming word-clock signal, which the converter is always trying to track. But with a USB controller generating its own word-clock signal, the frequency remains steady.

As I understand it properly, it's all about jitter, nothing more, nothing less.
 
According to Rankin, the S/PDIF environment is more prone to unwanted variations in the frequency of the incoming word-clock signal, which the converter is always trying to track. But with a USB controller generating its own word-clock signal, the frequency remains steady.

This is completely BS. USB is one of the most crappy interfaces, I've ever seen. It's a lowest cost, lowest quality, consumer interface connecting everything to the PC. Although SPDIF has it weaks details, it was designed for audio at least. With an USB interface you're getting uncontrolled ground loops as well as EMI coupling everywhere.
 
From the replies already posted, I gather that you realize that stereophile's opinion of what is the current state of the art is at best questionable. I don't remember reading a negative comment about a reviewed product for quite some time. And if you have read any of Dudley's other reviews you may get the impresssion that he just likes to read what he writes.
s/pdif isn't great but we're stuck with it. And now it's finally better than analog, so what's the problem?
 
I know how magazines work. I've been working for local coputer magazine for 4 years and I know that it's all about money. Magazine will never publish a negative review.

Anyway, the statement that USB is superior to S/PDIF made me think about it. And because I'm currently starting to work on my own DAC, I just asked.
 
My experience.....

I've been using a usb dac (Twindac plus) for over a year now. I can honestly say it's the best digital I've had at home. I use an iBook G4 to play back Apple Lossless files.
There are no issues with drivers at all. None. There is no noise from the computer or the usb or anything in my system. The entire playback chain is simple to use, reliable, and quiet.
My dac does convert usb to spdif internally and uses a very good clock to keep jitter low. I would like to hear a dac that is usb all the way through, but really...my digital sounds so good now, it's no big deal.
In the end, I think storing music on a hard drive is more important than the usb/spdif issue. If and it's a big IF, if you have a proper clock.
Steve
 
I second what Steve says. Playback from the computer is the way to go. The sound from my computer is awesome. Personally I don't see the point of overcomplicating things with USB. What is there to gain other than possibly some prevention of interference (that I have never actaully encountered in a computer based playback scheme).

Steve - slightly OT - do you find that you have to attenuate the Itunes playback? I am feeding my Behringer DEQ2496 straight from my G4 via SPDIF but curiously I find I have to lower the volume slider on itunes or the Behringer shows clipping on input. I find this puzzling since surely the SPDIF should be just pure digital and not require lowering or raising? Also I don't like the idea of attenuating using software. Do you have this experience?
 
>Steve - slightly OT - do you find that you have to attenuate the Itunes playback? I am >feeding my Behringer DEQ2496 straight from my G4 via SPDIF but curiously I find I >have to lower the volume slider on itunes or the Behringer shows clipping on input. I >find this puzzling since surely the SPDIF should be just pure digital and not require >lowering or raising? Also I don't like the idea of attenuating using software. Do you >have this experience?

I have the volume turned up all the way on both iTunes and the master in System Preferences. That means no digital attenuation right? I have no clipping issues. But I am using usb, not spdif.....I can't imagine why there would be a difference?
Steve
 
ChuckT said:
I also have an usb dac using pcm2706/tda1543 and I have to say it sound very good indeed. So no, usb interface does not suck.

PCM2706 looks good since it has IIS output, so there will be no problems with interface to DAC. I didn't know about this chip because I've been looking at 2704-05, which have just analog or s/pdif output (useless for me)

Thanks
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.